The authors have already proposed microwave nondestructive testing (NDT) method on detecting both location and degree of a pipe wall thinning (PWT) inside a metal pipe. However, problems caused by iofouling inside metal pipes are also frequ ently reported in recent years. As the existence of biofilm inside a aveguide will change its wave impedance and also cause microwave reflections, the characteristic signals of iofilm defects are studied here to distinguish the biofilm and PWT defects. A pair of coaxial...
英字タイトル:
Application of Microwaves on Remote and Nondestructive Testing of both Biofouling and Wall Thinning inside a Metal Pipe

We report a nondestructive method to measure the pipe wall-thinning (PWT) remotely using microwaves. A microwave vector network analyzer (VNA) and a self-designed transmitting and receiving (T&R) coaxial-line sensor are employed in the experi ment to generate microwave signals propagating in the metal pipe where the frequency was swept from 14.08 to 14.12 GHz. A brass pipe with inner diameter of 17.03 mm, 1.0 mm wall thickness, 2.0 m length, and connected respectively with 9 joints having the lengths of 17...
英字タイトル:
Remote Detection and High Precision Evaluation of WallThinning Volume in a Metal Pipe

Suppressing the stress corrosion cracking by reducing carbon contents in austenitic stainless steels seems to be not effective on core shrouds used in boiling water reactor in Japan. Trans-granul ar cracking was found out in the shrouds. To clarify a mechanism of the cracking, stress measurement on specimens under stretched condition in hot water has been attempted in the present study. A n in-situ device for diffraction measurements in synchrotron radiation facility has been developed by the present autho...
英字タイトル:
Effect of Surface Grinding on Residual Stress in Low Carbon Austenitic Stainless Steel SUS316L